Converting PBO fibers into carbon fibers by ultrafast carbonization

We report an ultrafast transformation of poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers into carbon fibers (CFs) by direct carbonization that eliminates high-cost oxidation in traditional CF conversion. Ultrafast heating and cooling render PBO-derived CFs superlative mechanical properties. ReaxFF atomistic-scale reactive molecular dynamics simulations unveil the PBO to CF conversion mechanism in which ultrafast heating suppresses the O-contained gas release, facilitating all-carbon rings alignment during the carbonization of PBO. These findings provide new guidelines for identifying and evaluating alternative CF precursors and fresh perspectives on smart manufacturing of CFs.